Image File Size Calculator — Raw, PNG and JPEG Estimates
Find out how large an image is — before and after compression. Enter pixel dimensions and color mode to get the exact uncompressed (raw) byte count, plus estimated file sizes for PNG lossless and JPEG at any quality level.
px
px
Color mode
Width × height × bits per pixel ÷ 8 — before any compression
- 1
Total pixels
1,920 × 1,080 = 2,073,600 - 2
Raw bits
2,073,600 × 24 bpp = 49,766,400 - 3
Raw bytes
49,766,400 ÷ 8 = 6,220,800 - 4
Raw size (MB)
6,220,800 ÷ 1,048,576 = 5.931 MB = 1,024 × 1,024 = 1,048,576 bytes.
How does this calculator work?
Image raw size = width × height × (bits per pixel) ÷ 8. A 1920×1080 standard RGB image is about 5.9 MB uncompressed. PNG reduces this to ~3.5 MB losslessly; JPEG at quality 80 reduces it to ~0.5 MB with minor visible loss. Sizes are bytes — multiply by 8 for bits.
Formula
How this is calculated
An uncompressed digital image stores one numeric value per channel per pixel. For standard 8-bit RGB (the most common mode), each pixel carries three 8-bit values — red, green, blue — totalling 24 bits or 3 bytes. Multiply by the total pixel count (width × height) to get the raw (uncompressed) size. Adding an alpha (transparency) channel brings it to 32 bits (4 bytes) per pixel; 16-bit HDR modes double the per-channel precision to 16 bits.
PNG uses lossless compression (DEFLATE), which typically reduces file size by roughly 30–50% for photographic content, or more for images with flat colour areas. The estimate here assumes ~40% reduction; actual results vary with image content.
JPEG uses lossy compression via the Discrete Cosine Transform. The quality parameter (1–100) controls the compression aggressiveness: quality 80 is a common default that yields good quality at around 90–95% reduction from raw. The size estimate here is an approximation based on typical photographic compression ratios — real JPEG sizes depend heavily on image complexity and colour variance. For precise results, use an image editor to export at your target quality.
Frequently asked questions
Camera raw formats (CR2, ARW, NEF, etc.) often store more than 8 bits per channel (typically 12 or 14 bits), plus metadata, colour profile data, and sometimes a full-size JPEG preview — all of which add to the file size beyond the raw pixel data this calculator computes.
PNG is lossless: it reduces file size without discarding any pixel information, so the decompressed image is bit-for-bit identical to the original. JPEG is lossy: it achieves much smaller file sizes by permanently discarding high-frequency detail. JPEG is ideal for photographs; PNG is better for screenshots, graphics with sharp edges, or anything requiring transparency.
Quality 70–85 is the typical sweet spot: it provides visually excellent results at roughly 10–20× compression relative to raw. Quality 90+ preserves fine detail for professional printing or archiving. Quality 50–65 is sufficient for web thumbnails where bandwidth matters more than sharpness. Below quality 50 artefacts become noticeable.
Also known as
TG we-Calculate Editorial Team. (2026). Image File Size Calculator — Raw, PNG and JPEG Estimates [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/image-file-size-calculator
TG we-Calculate Editorial Team. "Image File Size Calculator — Raw, PNG and JPEG Estimates." TG we-Calculate. 2026. https://we-calculate.com/calculator/image-file-size-calculator.
TG we-Calculate Editorial Team, "Image File Size Calculator — Raw, PNG and JPEG Estimates," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/image-file-size-calculator
@misc{wecalculate_image_file_size_calculator, title = {Image File Size Calculator — Raw, PNG and JPEG Estimates}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/image-file-size-calculator}}, year = {2026}, note = {TG we-Calculate} }
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